Wang Jie, Fan Huimei, Xia Siqi, Shao Jiahao, Tang Tao, Chen Li, Bai Xue, Sun Wenqiang, Jia Xianbo, Chen Shiyi, Lai Songjia
College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China.
Front Microbiol. 2022 Jul 6;13:888984. doi: 10.3389/fmicb.2022.888984. eCollection 2022.
In this study, diarrhea was induced in rabbits by feeding them antibiotic-free feed. The gut provides important defense against the barriers of the body, of which the duodenum is an important part to help digest food and absorb nutrients. However, the mechanisms underlying the roles of the gut microbiome and fecal metabolome in rabbit diarrhea caused by feeding an antibiotic-free diet have not been characterized. Recently, only a single study has been conducted to further characterize the antibiotic-free feed additives that caused diarrhea in weaned rabbits. The multi-omics techniques, including 16S rRNA sequencing, transcriptome sequencing, and LC-MS analysis, were combined to analyze the gut microbial compositions and functions. They also determined the fecal metabolomic profiles of diarrhea in rabbits caused by feeding antibiotic-free feed. The results showed that the liver, duodenal, and sacculus rotundus tissues of diarrhea rabbits were diseased, the composition of intestinal microbes was significantly changed, the diversity of intestinal microbes was decreased, and the distribution of intestinal microbe groups was changed. Functional analysis based on the cluster of GO and KEGG annotations suggested that two functional GO categories belonged to the metabolism cluster, and five KEGG pathways related to the metabolic pathways were significantly enriched in diarrhea rabbits. Moreover, real-time quantitative PCR (RT-qPCR) was used to verify the significant expression of genes related to diarrhea. Metabolomics profiling identified 432 significantly differently abundant metabolites in diarrhea rabbits, including amino acids and their derivatives. These amino acids were enriched in the tryptophan metabolic pathway. In addition, the functional correlation analysis showed that some altered gut microbiota families, such as , significantly correlated with alterations in fecal metabolites. Collectively, the results suggested that altered gut microbiota was associated with diarrhea caused by antibiotic-free feed additives in weaned rabbit pathogenesis.
在本研究中，通过给兔子喂食不含抗生素的饲料诱导腹泻。肠道为身体屏障提供重要防御，其中十二指肠是帮助消化食物和吸收营养的重要部分。然而，肠道微生物群和粪便代谢组在喂食不含抗生素饮食引起的兔子腹泻中所起作用的潜在机制尚未得到表征。最近，仅进行了一项研究以进一步表征导致断奶兔子腹泻的不含抗生素的饲料添加剂。结合了包括16S rRNA测序、转录组测序和液相色谱-质谱分析在内的多组学技术，以分析肠道微生物组成和功能。他们还确定了喂食不含抗生素饲料引起的兔子腹泻的粪便代谢组学特征。结果表明，腹泻兔子的肝脏、十二指肠和圆小囊组织出现病变，肠道微生物组成发生显著变化，肠道微生物多样性降低，肠道微生物群分布改变。基于基因本体论（GO）和京都基因与基因组百科全书（KEGG）注释聚类的功能分析表明，两个功能GO类别属于代谢聚类，与代谢途径相关的五条KEGG途径在腹泻兔子中显著富集。此外，使用实时定量PCR（RT-qPCR）验证与腹泻相关基因的显著表达。代谢组学分析在腹泻兔子中鉴定出432种显著不同丰度的代谢物，包括氨基酸及其衍生物。这些氨基酸在色氨酸代谢途径中富集。此外，功能相关性分析表明，一些改变的肠道微生物群家族，如 ，与粪便代谢物的改变显著相关。总体而言，结果表明肠道微生物群改变与断奶兔子发病机制中不含抗生素的饲料添加剂引起的腹泻有关。
